Day disclosed an automatic single push button type umbrella in his U.S. Pat. No. 4,823,821 which is expanded by spring action and collapsed by spring action. Both spring actions are initiated by a single push button which is manually manipulated in the same manner for initiating both spring actions.
Besides a false operation possibly being made by Day's umbrella, for instance, a suddenly continuous depression of the button 6 or uncareful push button operation which may first open the umbrella and then close the umbrella quickly, Day's umbrella did not provide any means for holding the tips of rib assembly 5 towards the shaft 3 approximate to the grip 31 when the umbrella is closed. There is no suitable space for providing a tip cap slidably held on the cylindrical wall 35 of the grip 31 for fastening the folded tips of rib 5 so that the ribs 5 even after being collapsed may still be slightly extended as shown in his FIG. 1, possibly obstructing an environmental object or even stick and injure the user or someone standing nearby especially on a crowded city bus.
The present inventor has found the drawbacks of such a conventional automatic umbrella, and invented the present automatic umbrella which is foldably retained by a tip cap.